Semporna Archipelago, Borneo

Located off the coast of the Malaysian state of Sabah, this is where giant sea turtles swim alongside schools of sleek reef sharks, and vertical walls drop thousands of meters from the edge of powder-soft beaches into mysterious blue depths.

The best known snorkeling and dive islands are Mabul and Sipidan, located in the southern end of the archipelago. Stay at one of a handful of dive resorts in Mabul, since tourists are not allowed to sleep on the protected island of Sipidan (the government allows only 120 passes to the island a day, which you should secure in advance from a dive resort). We recommend Borneo Divers, the original operators for the region who first introduced ocean explorer Jacques Cousteau to Sipidan, and catapulted the destination into the stuff of diving legend. Mabul offers some spectacular muck-diving around an old oil rig that’s been converted into an off-shore hotel. However, Sipidan is what really attracts divers from across the globe, with famous dive sites such as Barracuda Point where you can literally swim in the eye of a tornado-shaped formation of circling barracuda flesh.